Pump.



No. 784,178. PATENTED MAR. 7, 1905. A. RADUVANOVIG.

PUMP.

APPLICATION FILED NOV. 2, 1904.

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Patented March *7, 190%,

ANDREAS RADOVANOVIG, OF ZURICH. SWVHTZERLANI).

Fltllllll n SPECIFICATION forming part of Letters Patent No. 784,178, dated March 7, 1905.

Application filed November 2, 1904. Serial No. 231,139.

To all whont if; m/rr-y concern:

Be it known that I, A no 1: ms RAnovANovIo, a subject of the Emperor of Austria-Hungary. residing at Zurich, Switzerland, have invented certain new and useful Improvements in Pumps, 01 which the following is a specification.

This invention relates to pumps with means For closing the suction-valve by hydraulic pressure, and according thereto a pump is provided with a plunger-cylinder communieating with the pressure-chamber and being closed against the pump-chamber by a plunger-piston forn'iingan extension of the pumppiston. By means of radial channels, which are only uncovered at the position of the pump-piston corresponding with the end of the suction-stroke, the dunger-cylinder communicates with a cylinder the piston of which isiormed by a projection of the suction-valve, so that the closing of this valve is cli'ected at the end of the suction-stroke.

In the accompanying drawings, which illustrate examples of apparatus according to this invention, Figure 1 is a vertical longitudinal section of such a pump. Fig. 2 is a detail view showing a modified structure of. one part oi. the pump; and Fig. 3 is vertical 1ongitudinal section of a modified constructional form of a pump according to the invention, the delivery-valve not being shown.

The pump-chamber m, as shown in Fig. 1,

provided on its top with a delivery-valve and on the bottom with a suction-valve. The pump-piston p is provided with an extension forming the plunger-piston p. The latter [its into a cylinder 0, which communicates by the conduit Z with the pressure-chamber situated above the delivery-valve and by radial channels or holes 1) with the cylinder a. The holes p are disposed in the cylinderrin such a manner relatively to the plunger-piston that these holes communicate with the side of the plunger-cylinder communicating with the pressure-conduit only at the outermost or extreme position of the plunger-piston, (shown in the drawings,) which position corresponds with the end of the suction-stroke of the pump-piston. 1n the cylinder a may move the piston Zr, forming a rigid projection of the suction-valve. This arrangementoperate. as follows: At the end of thesuctiou-stroke the radial holes 7.)" are uncovered by the plungerpiston j), whereby the fluid under pressure gains entrance from the conduit l and from the cylinder '1' into the cylinder (0, where it acts on the piston 7*, and thereby causes the suction-valve to close.

In the modified constructional form shown in Fig. 2 the cylinder a is provided with radial holes 0, which are disposed relatively to the piston Zr oi the suction-valve in such a manner that they are uncovered at the closed position of the suction-valve. This arrangement operates as follows: The pressure fluid flows first from the pressure-conduit into the cylinder (0 and causes the closing of the suction-valve, as described; but prior to the moment of the complete closing of the suctionvalve the piston Z: uncovers the holes 0 oi the cylinder a. Now the pressure fluid is able to flow into the pum i-chamber m, so that the pump-piston at the beginning of the pressure-' stroke meets the full pressure in the chamber m.

Fig. 3 shows a constructional form of the pump wherein the suction-valve is disposed coaxial with the pump-piston 71. in this case the piston X: has an annular shape and may transmit the H u id-pressure to the suction-val vc by means of an elastic buffer/1. After the closing of the SUCtlOIl-VitlVO (this position is shown in Fig. 3) the butler 7), situated between the piston Z; and the suction-valve, is further compressed by the fluid-pressure. The piston Z: moves still farther to the right and uncovers an annular opening 1*, through which the pressure liuid flows into the pumpchamber.

In case where an elastic connection is provided between the piston Z: (shown in Fig. 2) and the suction-valve the arrangement may be such that at the moment of the closing of the suction-valve the piston 71 is still covering the holes 0 and uncovers the latter only when theelasticbutier. situated between the piston and the suction-valve, is compressed by the hydraulic pressure in the cylinder a. By suitably selecting the cross sections or areas of the holes 7) and 0 and by causing the uncovering of these holes in due time it can be attained that the suction-valve is closed just at the moment of the reversing of the stroke, so that the full pump-pressure is obtained in the chamber m, and any hammering is prevented when the pump is running.

By the described arrangement of the pressure-fluid supply the effect is produced that the pressure fluid continuously presses on the working area of the piston 32, so that the pump rods even at the suction period are strained, but only in one direction, and therefore do not sufler by reverse of pressure.

The relative position of the suction-valve, or eventually of a number of suction-valves, and of the axis of the pump-plunger can be arranged as desired.

The described closing of the suction-valve by hydraulic pressure can be employed with pumps and valves of all kind.

I claim 1. In a hydraulic pump, the combination with a forcing piston, pressure and pump chambers and suction and delivery valves, of means controlled by the piston to admit water under pressure to the suction-valve, the pressure of said water being greater than the pressure of the water in the suction-chamber and means controlled by the movement of the suction-valve to vent said water under pressure into the pump-chamber, substantially as described.

2. In' a hydraulic pump, the combination with a forcing piston, pressure and pump chambers, and suction and delivery valves, of a connection between the suction-valve and pressure-chamber, and a valve on the end of the piston to admit water from the pressurechamber to the suction-valve to close the same, substantially as described.

3. In a hydraulic pump, the combination with a forcing piston, pressure and pump chambers, and suction and delivery valves, of

means to admit water from the pressurechamber to the suction-valve and means controlled by the movement of said valve to vent said water into the pump-chamber, substantially as described.

4. In a pump, the combination with a forcing-piston, pressure and pump chambers, and suction and delivery valves, of means controlled by the piston to admit Water from the pressure-chamber to the suction-valve to close the same and means controlled by the movement of said valve to vent said water into the pump-chamber, substantially as described.

5. In a pump, the combination with a forcing-piston, pressure and pump chambers, and suction and delivery valves, of a cylinder connected to the pressure-chamber, and a piston cooperating therewith, said piston connected to the suction-valve and a valve on the end of the forcing-piston to admit water under a pressure greater than the pressure in the pumpchamber, to said piston to close the suctionvalve, substantially as described.

6. In a pump, the combination with a forcing-piston, pressure and pump chambers, and suction and delivery valves, of a cylinderhaving outlet-ports and a piston cooperating with the cylinder, said piston connected to the suction-valve and a valve controlled by the forcing-piston to admit water under pressure into the pump-chamber to said piston, to close the suction-valve and open the ports in the cylinder to vent the Water under pressure into the pump-chamber, substantially as described.

7. In a pump, the combination with a forcing-piston, pressure and pump chambers, and suction and delivery valves, of a ported valvecasing, a pipe connecting the casing with the pressure-chamber, a piston-valve in said casing and forming an extension of the forcingpiston, a cylinder and a piston cooperating therewitlnsaid cylinder connected to the valvecasing, whereby water from the pressurechamber will be admitted to the piston to close the suctionvalve, substantially as described.

8. In a-pump, the combination with a forcing-piston, pressure and pump chambers, and suction and delivery valves, of a ported cylindrical valve-casing, a pipe connecting one end of the casing with the pressuire-chamber, a

piston-valve in said casing forming an extension of the forcing-piston, a cylinder and a piston cooperating therewith, said cylinder connected to the valvecasing and means controlled by the piston to vent water from the pressure chamber into the pump chamber, substantially as described.

9. In a pump, the combination with a forcing-piston, pressure and pump chambers, and suction and delivery valves, of a ported cylindrical valve-casing, a pipe connecting the casing and pressure chambers, acylinder forming an extension of the valve-casing, a piston external of said cylinder and connected to the suction-valve, and a piston-valve forming an extension of the forcing-piston to admit water from the pressure-chamber to the piston connected to the suction-valve and move said piston to vent the water into the pump-chamber, substantially as described.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

ANDREAS RADOVANOVIU. \Vitnesses:

A. LIEBERKNECHT, V. KARMIN. 

